Arc extinguisher



Patented Oct. 19, 1943 UNITED STATES PATENT OFFICE I v ARCQ'EXTINGIYJISHVER Ralph Pittman, H I Application September 18, 1941,"Serial lflo341i351 7 Claims.

' This invention relates generally to lightningprotection devices, and more particularly to devices for the purpose of limiting the voltage of an energized conductor by means of sparkover gaps adapted to break down at a predetermined voltage, together with means for quickly extinguishing any arc which may follow breakdown of the gaps. The-device described herein is particularly adapted for draining excessive superimposed voltages from transmission line conductors;

Devices for-the latter and similiar purposes have heretofore been widely used. These devices generally include a straight linear breakdown or initial path of uniform cross-section in which it is intended to extinguish an arc following breakdown. The performance of the two essential functions, viz., limiting of voltageand are extinguishment in the same path imposes serious limitations on such devices, so that, if effective for one function, they operate poorly or not at all with respect to the other. As a result, the devices are necessarily a compromise, and'as nowavail-- able, have a restricted range of current interruptingability which is determined by the initial breakdown voltage.

sparkover path for the purpose of'limiting thevoltage impressed on the device, together an arc-extinguishing path differing from that of the sparkover path, enabling each'structure to and at the same time enabling arc-extinguishmentto be accomplished within a cooperating structure sothat the erosion attending arc-extinguishment doestnot adversely affect the ref peated operation of the device.

,Other objects and advantages of my invention will be apparent from the following description,- and the scope of the invention will be indicatedin the appended claims.

vIn the drawing: Fig. 1 is a side elevational: View of the device, most of which is shown in sec tion; Fig. 2,is a section taken along the line IIII of Fig. 1; Fig. 3 is a plan view of the device, as'seen from below; and Fig. 4 illustrates a: method of applying the device to a'transmission' line conductor.

} Referring to the drawing inmore detaiLtwo hollow tubular insulators l and. l6,,which..may.

It is an object of the pres ent invention to provide a structureembodyi'ng a a conductorassociated with with a structure embodying difier both in length and internal mameterge're' each provided-at "their respective lower ends; with the-hollow'lower electrodes I 3 and- 20 of conducting inaterial, these electrodes being secured to the respective insulators by cooperating threads-on the-respectivemembers. {The openine o electrode 'l Sis incommunication with-hollow l of the longer meanes -later "I llfand methan ing 'z| 0f :tl%1e electrode 2L0 similarly arranged in communication with the hollow I 1 of theother i f ing'tflb la fi su etq afe r fe a arranged in spaced parallel; or side by side rel a. tionshipgfzt; threaded portion of their respective; electrodes l3 and 2d extend-ing downwardly through spaced openings- "the metal mounting bracket 22.;For maintaining the tubular insula-' tors in spaced parallel-'- upstanding position,- a portion 'fof the bracket: 22 -isfclarnped between the nut 23,-inthreaded engagement with an exten; nally' threaded downwardly extending portionand an outwardly extending of the electrode [3, v

g In "similar, fashion," nut' 23- cooperates with the 'el ctrode 20 for clamping another portion. of" the" bracket ".22, j The" tubular insulators l0 and] 6 are in this manner supported fromtheir lower ends, with; their faxes in spaced parallelrelation to each other, trodes of each insulator beingtubular insulator lll by means of the engagement ofan externally threaded downwardly extending portion ofthe electrode with cooperating internal* threads in the tubular insulaton; and e the con ducting-electrode l8 is-similarly arranged with p'e fi' th u es sl l6- Atafpoint near -the-upperend of the tubular insulator l 8 trodes-l2- and' l3'of the tubular insulator lllQ-a' first" intermediate condu ctirigelectrode I5 extends laterally through the- -wan of'tlietubular insulator 1 ill. The electrode 1 5 may conveniently thi'ejacledlyengage the opening of the wall tnrbugh'wnien it passeaand an integral 5 portion" I 9 r me": electrode" 1 8 extends toward the insulator -ill and positionfi for. engagement 5 by the electrode i l5, thereby electrically connecting the electrbdesffli 2.11df|,8."',"."

. Thei'nsulating attain; used nae ename: tionofithe' tubular insulators 1 L0: and lids pref-y the lower elec r electri ally 'cong' nected'through the intervening portion of the" V em'ciaita point between and inspacedi insulated --relationship with respect to the elec upwardly along its outer wall-tola erably one which has a high resistance to heat and which evolves cooling gases in the presence of an arc. Hard fiber is one such material.

Fig. 4 illustrates an arrangement for applying the device, indicated here in its entirety by the reference character 28, for the purpose of limiting the voltage on the transmission line conductor 3|, the latter being supported in accordance with common practice from the crossarm 25 by the insulator. string .26. So applied the are extinguishefi Z8 is supported in an upright position by bolting the vertically extending portion of the bracket 22 to the crossarm 21 by means qt the bolt 30, the upper end of the arc extinguisher 28 extending to a point near conductor 3|.

but spaced fromtll" The lower electrodes of thedevice.

28, being in engagement with the bracket itma'y" be conveniently maintained at ground 30 to the ground, here by connecting the bolt symbolically indicated at 29, through the ground- 5. QQRQQQEQ; .:.i.; .flha-tit oma otraozomooi. osuoh. tha

h or anizat on mo ti t. oi' o. o o t rraosoa oil current circuit, an arc.

eizlio'ol o a aliena in t iator; may eoi o a t evorkovor, e n 99 the point of the cycle at whichbreakdownioccurs. If an ar'cfo'cours, o g sparkove j" 11 3;. gases e lieodiiej t'nife ne rer wears are. x-f' pelled 'frointhe upper portion oi the tubular sui'atdr "mi dt iwnwardlyj through the 'vjeii't. r4 Tn gases are initially, 'o'r' before'j substantial i ins ore within m' or pressure is tuneup con uetmger'wmcn' wm eu a- 4 H p s; lro'f the current'pa ssfijjf h ou hany fo 'iiloi' 'f n t e hollow botf i the e ctrodes 12 and. i5, since; a pr'ac' a1. matter, tw'darcs insueh e patella arraflso Winn mainta'mfi Since the quantity, of electricity in a st'rjogjuecaus of 'the. short time or its existence,

that to. i ioa i hoi i fir t, o 'Pioothe hollow l1 asn'es'ult oi, the shunting efiegt ocioo no; owe Port on o tho ieor tf r "1 m; han; o .o fi fso h o y. ea. oo i t on. within ho oo o r '0- As p. example, for tl fiqp voli operation, the insulator IQ may. be... Pro ded; wi h n. t rn e the. rd r oi /af' n di m te a d h w emeal: lator Htwith a much largerbore, of the order. or it mu tim ter. re diameters in quired. as the striking ditances are increased for useon hi hervolta es- By thisor aniz io o r tir. calt portion of the initialbreakdown pathintha hollowlfb is not. subjected to damagingerosiom. even though of small diameter, and may there.- fore be reduced in length to almost. the limiting pointatwhich an arc within it is notextinguishedj by the shunting effect of the larger bore insulator with which it cooperates and is coordinated.

The transfer of the arc current from its initial path in the hollow l! to its final path between the electrodes I5 and I3 is extremely rapid, the elapsed time being a small fraction of a cycle, and the entire sequence of events including initial sparkover, arc transfer, and final extinguishment occurs within 2; cycle or less, final extinguishrnent occurring. atthe first current zero.

The above desc'riptioni intended to be illustrative rather than limiting. I claim as my invention: 7

"1. An arc extinguishing device comprising at hastens hollow tubular insulators, means supporting. saidtubular insulators in side by side rel'ationshipfnorinally insulated conducting electrodes. associated with each of said tubular insulators including one electrode secured at the upper "end of one insulator and extending downwardtv. int the hollow hereoin .smced relation ithitsloaer. o -c' nd another elecutodesecwd at he. lowe en zoiitho "o he insulat r; and stnm. ta sa moans. tor: ca sing chemical; breakdown hrou h. the. devi e-to. occ r. ove an. initialized: ithin. an. REFER. ort or sa dooennauatm. and. a loirorp xtion i' fid' fiifqthellinsulator; sa'id ructural meansin udin fittes in ermediate ectrode. extendin .aterally thr u h-the. wall. n into hol ow. or sa d; one insulato at. a; point below said one electrode in spaced inane; atod. olo ionahin ther with. a second iate. ele trode ex end ng; d whwardhtffmm; the. unmet. end. oil' aid' other anu a etin spaced in:

la ions-hipwith. saidiano hen electrode; ndm ans resn nsi c. to the. occurrence. of an a c: said ot e nsulator. following break-. own. ov r th initialath or. extinguishing'said. am a d. antenamed means. including. a. lower leotrodos se lkrediatthedower. end at. said one, ns la or. a

. a onrmuoieauon, with. thahollow. hoxoot means el tricallr. connec nmsm afer. olootl'od tosa deoother. eleetmdel .1- An. arcextineoisbina dbvificcomprislng .trm hol ow. ubu ar: nsulators, meamsupporun said tubular in ulators side by siderelauonshin, mor nsulat doonduotine electrodes. associated with each izsaidtub aar insulators. including. one. leotroste eomiedatandclosing the; upper endfofs oa nsulator. and-extending. downwardly. into lowa heteo oaceditelatlonwitn its lower. nd and; ano hen.e eotrodesecured at the. lower. n soii othelt'insulfitoa. andistructnral. menu or.'oausinaeleotrical.hreakdownthr uznownai ir-11mm nott onot aid. ona nsulator. .anma. lower, portion solo-o her in ul to said; structuralmeana udioe. adi st intermediate. electrodeextendinaatoralls thr ushthe-wall. .ot one. insulator. .8 oint; between its, ends. and. below saidcone. ec rod in. h med. insulated.- lfilfltmnshipllllfil'fla w a se d nnediateelectmde. closing-hm. Reverend of... oi 1-.. otheninsu amnand extendin downwards theretmm in. spaced, insulated. relas id; anotherpelectrcde. :and mean; responsive to the occurrence oianarnwlthmsafl m...inul. tm. following. breakdown. .oveic said itial Pa h. for: extineuishingsaid; are, saidclasfnamed meansincluding .alower electrode securedat: theilower: end of; said one insulator. and-iii c.ommunication.. with.i the hollowthereofandmeans electrically connecting; said lower use: trode to said another electrode.

' 3; An arc extinguishing devicecornprising-two, hollow tubularifisulators;"meahs-' supparnh'san cluding one electrode secured at the upper-end of-one insulator and extendin'g'idownwardly into thehollow thereof inspaced-relation with its lower end and another electrode securedrat. the low'er'end of the other insulaton'and structural means for causingelectrical breakdown through thedevice to occur over an initial path which in cludes in series circuitrelationship ari upper portion of the hollow of said one insulator and a lower portion of the hollow of said other insulator, said structural means including a first intermediate electrode extending laterally through the wall of said one insulator at a point below said one electrode in spaced insulated relationship therewith, a, second intermediate electrode closing the upper end of said other insulator and extending downwardly therefrom in spaced insulated relationship with said another electrode, and means responsive to the occurrence of an arc Within each of said insulators following breakdown over said initial path for extinguishing the arc within said other insulator, said last-named means including a lower electrode secured at the lower end of said one insulator in spaced insulated relationship with said first intermediate electrode and in communication with the hollow of said one insulator, and a conducting member electrically connecting said lower electrode to said another,

electrode.

4. An arc extinguishing device comprising two hollow tubular insulators of unequal length, means supporting said tubular insulators in substantially parallel relationship, normally insulated conducting electrodes associated with each of said tubular insulators including one electrode secured at the upper end of the longer insulator and extending downwardly into the hollow thereof in spaced relation with its lower end and another electrode secured at the lower end of the other insulator, and structural means for causing electrical breakdown through the device to occur over an initial path which includes in series circuit relationship an upper portion of the hollow of said longer insulator and a lower portion of the hollow of said other insulator, said structural means including a first intermediate electrode extending laterally through the wall of said longer insulator at a point below said one electrode in spaced insulated relationship therewith, a second intermediate electrode closing the upper end of said other insulator and extending downwardly therefrom in spaced insulated relationship with said another electrode, and a conducting member electrically connecting the intermediate electrodes, and means responsive to the occurrence of an are within each of said insulators following breakdown over said initial path for extinguishing the are within said other insulator, said last-named means including a lower electrode secured at the lower end of said longer insulator in spaced insulated relationship with said first intermediate electrode and in communication with the hollow of said longer insulator, and a conducting member electrically connecting said lower electrode to said another electrode.

5. Marc extinguishing device comprising two -hollow tubular insulators, one of said insulators being longer than the other and the diameter of the longer insulator being greater than that of the other, means supporting said tubular insulators in substantially parallel relationship, normally insulated conducting electrodes associated with each-of said? tubular insulators including. one electrode securedi at and closinggtheupper end:of the longer insulator and extending downwardly into the "hollow thereof-Lin spaced :relation; .Jwith itslower end and another electrode secured'cat the lower end of the other insulator, and structural "meanswfor' l'caus'inga: electrical breakdown through the device to occur, 'over'an initial-path which includes in series circuit relationian upper portion of the hollow of said longer. insulator and a lower portionxof the hollow; of said-other insulator, said. structuraljmeansincluding a first intermediate electrode extending laterally through the wall of said longer insulatorv at a point below said one electrode in spaced insulated relationship therewith, a second intermediate electrode closing the upper end of said other insulator and extending downwardly therefrom in spaced insulated relationship with said another electrode, and conducting means electrically connecting the intermediate electrodes, and. means responsive to the establishment of an arc within each of said insulators following breakdown over said initial path for extinguishing the are within said other insulator, said last-named means including a lower electrode secured at the lower end of said 1 closing the upper end of the longer insulator and extending downwardly into the hollow thereof in spaced relation with its lower end and another electrode secured at the lower end of the other insulator, and structural means for causing electrical breakdown through the device to occur over an initial path which includes in series circuit relation an upper portion of the hollow of said longer insulator and a lower portion of the hollow of said other insulator, said structural means including a first intermediate electrode extending laterally through the wall of said longer insulator at a point below said one electrode in spaced insulated relationship therewith, a second intermediate electrode closing the upper end of said other insulator and extending downwardly therefrom in spaced insulated relationship with said another electrode, and conducting means electrically connecting the intermediate electrodes, and means responsive to the occurrence of an arc within each of said insulators following breakdown over said initial path for extinguishing the arc within said other insulator, said lastnamed means including a lower electrode secured at the lower end of said longer insulator in spaced insulated relationship with said first intermediate electrode and in communication with the hollow .of said longer insulator, and a conducting member electrically connecting said lower electrode to said another electrode, said conducting member being constructed and arranged to support said insulators in substantial parallel relationship from the respective lower ends thereof.

7. An arc extinguisher comprising two separate and distinct tubes of an insulating material which evolves gas in the presence of an arc, said tubes diflenna both mmmmlldimher .smtlonxfih; snmeitiimmisdd .fustuand aid lower elwtrode; means supportingjuld tum-munmdiurmh tram the. auts dc oi said 10mm atantially pan-9.1mv relationship. mxflrstrnmzliy insulam;m; amaim; in communicationwith the insulated conducting alumnae mnrslrxb and hnllcm'thcmof, mmintermediate electrode mclosingthe uppermd oiflwlonaex tubemmond 5 opnrm'vdth said'firshmd secqnd; eleotrodw normally insulated conducting electmdmmued tor mitiatmafiamrimary' am within. t e-hollow at o nd i e-P nman: the; stmrtazztuhe; the Imam: tub: in series cimuitmlation wit said lb'wer conducting electrodes; mm'edsat :thcnb inmmadiam elemmdahandxausing disqharze 01 spective Inner enda of said when; sidiowetelnm mm'isn pafll whinhis in shunt circuit xetrodes beinznormall'ymamated-ztrnmcmdrfimt m kflomwithmq minterm diate. elcctrode. and m and second conductint. electmdzx. meansaem sfidtfilitmiiirmlfl'timflliflr saddprimnrywe. trically connecting aaidilnwar. electrodes; an'im v V tarmediate' rconduntinz. electrode xmrmflhfln I RAL HR PITIMAN. 

